Electric fitting



Oct. 6, 1936. F. A. RENO ELECTRIC FITTING Filed Feb. 8, 1955 Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE 3 Claims.

The present invention relates in general to an electrical fitting and is particularly concerned with an improved fitting of the type having a screw plug connection and a single two circuit 5 socket or a pair of single circuit socket connections for receiving the screw base of an incandescent lamp, plugs etc.

More specifically, the fitting of this invention contains within its shell housing, an automatic switch which is connected in the circuit through the fitting in such a manner as to automatically disconnect the supply circuit from one of the socket circuits, when that socket circuit is interrupted, and connect the supply circuit to the other socket circuit.

The device or attachment of this invention is susceptible of myriad uses, and may, for example, be used to provide a main and auxiliary source of illumination by simply screwing an incandescent lamp into each of the double sockets l,

or a two filament lamp into the double circuit socket type. When the main source of illumination or the main lamp is burned out or its circuit otherwise interrupted, the automatic switch therein automatically connects the auxiliary lamp into the circuit.

,The fitting may also be utilized to energize a signal circuit, when the main circuit is interrupted. For example, the main circuit might feed the tail light of an automobile, a second light being provided in the circuit and mounted on the dash of the automobile so that when the tail light for any reason goes out, the signal light on the dash will be lighted. Similarly, the device s applicable to the operation of burglar alarms and other signal apparatus.

Although, the invention is primarily shown as being utilized in connection with incandescent lamps, it will be readily apparent to those skilled i0 in the art that other current consuming devices may with equal facility be substituted for the incandescent lamps, depending upon the conditions under which the attachment is to be used.

It is a principal object of the invention to provide a self-contained electrical fitting embodying an automatic throw over switch, whereby upon the de-energization of a main circuit, an auxiliary circuit will be energized.

It is a further object of the invention to provide 5o a fitting of the herein described character, which when not used in its particular capacity, may be Y utilized as the usual fitting of this type not having the throw over feature.

Other objects and features of this invention will more fully appear from the following detailed (Cl. 20G-87) description taken in connection with the accompanying drawing which illustrates several embodiments thereof, and in which:

Figure 1 is a large view of the fitting showing parts in elevation and having cutaway portions c in sections to show the operative details of the associated instrumentalities thereof, this view showing a device adapted for use with a double filament incandescent lamp;

Figure 2 is a modified arrangement utilizing 1u two outlet sockets instead of a single double circuit socket;

Figure 3 is a schematic diagram illustrating the electrical connections of the fitting;

Figure 4 is an enlarged view of the operating lo coil and the associated movable contact controlled thereby, portions of the coll being cut away to disclose details ofconstruction; and

Figure 5 is a transverse cross section taken through the solenoid plunger of the operating 20 mechanism. p

As shown on the drawing:

In the form of the invention illustrated in Figure 1, the electrical fitting is disclosed as comprising a shell like structure I0 which is prefer- 25 ably constructed of an insulating material, and fitted at one end with a plug connection or base of the usual construction comprising a screw thread contact I I and a central point contact I2.

At the lower end of the fitting, the shell IIl is formed to define a socket I3 in which there is mounted a screw thread sleeve I4 of the usual construction, this sleeve forming a contact into which the threaded base contact I5 of an incandescent lamp I6 may be screwed. 35

In this particular instance, the lamp I6 is of the two filament type comprising a main filament Il and an auxiliary or secondary filament I8.

One end of each filament is connected to the screw base contact I5 and the other end of the main filament is connected to a centrally disposed and insulated contact pin I9, whereas the other end of the secondary or auxiliary filament is connected to the usual contact ring 20.

Electrical connections are made from the 45` are so disposed as to respectively cooperate with contact members 20o and I9 of the lamp base.

The insulating member 23 is formed with a pair of spaced leg portions 26 and 21 which cooperate to form a supporting bracket structure for a solenoid coil 28 having a hollow core construction for reciprocably receiving therein a solenoid 29. 'Ihe member 23 and the legs 26 and 21 have portions in frictional engagement with the interior surface of the shell l0, whereby the solenoid and associated contacts are frictionally supported as a unit within the shell. Y

This solenoid is of tubular construction and along one side is provided with a longitudinally extending slot 30 for preventing ow of circulating or eddy currents which would cause the solenoid core to become heated. ,One end of the solenoid forms a solid extension 3| upon the outer end of which there is plvoted a disc shaped contact member 32. The disc is so mounted that it may be tilted as shown in dotted lines relative to its central pivot, thereby making the contact self-aligning. Normally, the contact 32 together with the solenoid is moved outwardly under the inuence of a compression spring 33 having one end abutting the coil structure and its other end abutting the contact disc 32. It will be seen that this spring also tends to maintain the contactdisc 32 in a position normal to its pivot. Y

The contact point I2 is connected by means of conducting members 34 and 35 to the contact 24.

It will be observed `that the free ends of these conductors are disposed immediately under the disc contact 32 so that when the disc 32 is moved downwardly under the inuence of the spring 33, the circuit will be completed from contact point l 2 to contact 24, but when the coil 28 is energized and the contact 32 is raised, this circuit will be interrupted.

One end of the coil 28 is connected' to conductor 34 and the other end of the coil is connected to contact 25.

From'the foregoing description, it will be seen that when the main iilament l1 is energized, the coil 28 which is in series with the main lament, will also be energized to open the circuit through conductors 34 and 35 to contact 24 which is in circuit with the main or primary filament. Should the main filament, however, be burned out for any reason, the coil 28 will be de-energized and the spring 33 will force contact 32 into engagement with the free ends of conductors 34 and 35 and immediately connect the auxiliary or secondarylament I8 into the circuit.

Figure 2 shows a modified arrangement wherein the shell structure is formed to deine'angular- 1y disposed single circuit sockets for respectively receiving a single lament lamp 36 and plug connector 31, instead of a single double circuit socket as shown in Figure 1.

In the modied form, corresponding numbers have been used to indicate parts corresponding to those shown in Figure 1.

The plug connector 31 may be utilized for making circuit connections to remotely located lamps or other elec fical devices of a current consuming nature, if desired, an auxiliary lamp may be inserted in the socket in place of the plug 31.

In this form of the invention, the coil 28 is supported on a bracket such as shown at 38, and it will be observed that the screw socket contacts I4 and I4 are interconnected by a conductor 39.

In both the preferred and modified forms, the

plug and socket connections are disclosed as being of the screw type. It is contemplated, however, that any of the various and well-known types of connection such as bayonet connections and others may be used. Y

Referring to Figure 3, the electrical connections between the various parts of the invention are shown. It will be observed that the invention may be utilized to control a main source of illumination such as an incandescent lamp 36 and an auxiliary source of illumination such as an incandescent lamp 36'. The lamps 36 and 36 are connected in parallel across an electrical circuit 40. In'series with the main lamp 36 is the operating coil 28 of the switch mechanism. The movable contact 32 is arranged to close the parallel circuit through the auxiliary lamp 36 when the coil 28 is deenergized by a burning out of the main lamp 36 or otherwise opening its is deenergized, the spring 33 moves the contact 32 into closed cooperation with the associated contacts in the parallel circuit of auxiliary lamp 36'. 'The auxiliary lamp is thereupon lighted, the source of supply being from the lelectrical circuit 40.

From the foregoing description, it will be apparent that this invention provides a novel electric iitting which embodies an automatic switch for automatically transferring the supply circuit Vto an auxiliary circuit, when the main circuit is interrupted; a tting which, when it is not used for the special purpose for which it is adapted, may -be used in the same manner as the usual tting of this type; and a fitting which is 4adapted for use in signal circuits and a great number of diierent arrangements, wherein it is desired to quickly and easily provide an arrangement for connecting` a supply circuit either to a main outlet or an auxiliary outlet, when the main outlet circuit is interrupted, without the necessity of expensive and special wiring.

Now, of course, it is to be understood that while the invention is illustrated and described in detail in a preferred and modied form, the invention is not to be thus limited but only insofar as dened by the scope and spirit of the appended claims.

I claim as my invention:

1. As an article of manufacture, an electrical fitting having a single circuit inlet connection and double circuit outlet connections; said fitting comprising a main elongated shell portion of substantially tubular construction, an inwardly extending abutment shoulder formed on the interior surface of the shell, a disk of insulating material abutting the shoulder and held in position by the engagement of its periphery with the interior of the shell, a solenoid coil within the shell connected in series in one ofthe outlet circuits, a pair of coil supporting brackets carried by said disk, a pair of spaced contacts connected in series in the other outlet circuit, a solenoid core operatively associated with said coil, a contact carried by said core adapted to bridge the spaced contacts, when the c oil is de-energized, and open the circuit through the spaced contacts, when the coil is energized, and spring means for moving the core in a direction to bring the bridging contact into bridging position, when the coil is deenergized.

2. As an article of manufacture, an electrical fitting having a single circuit inlet connection and double circuit outlet connections; said fitting comprising a main elongated shell portion of sub- 7.5

stantially tubular construction, an inwardly extending abutment shoulder formed on the interior surface of the shell, a disk of insulating material abutting. the shoulder and held in position by the engagement of its periphery with the interior of the shell, a solenoid coil within the shell connected in seriesv in one of the outlet circuits, a pair of coil supporting brackets carried by said disk, said brackets making frictional engagement with the interior of the shell to augment the holding action of the disk, a pair of spaced contacts connected in series in the other outlet circuit, a solenoid core operatively associated with said coil, a contact carried by said core adapted to bridge the spaced contacts, when the coil is de-ene-rgized, and open the circuit through the spaced contacts, when the coil is energized and spring means for moving the core in a direction to bring the bridging contact into bridging position, when the coil is de-energized.

3. As an article of manufacture, an electrical fitting having a single circuit inlet connection and double circuit outlet connections; said fitting comprising a tubular shell having an internal shoulder adjacent one end, an' insulating disk abutting said shoulder, switch means supported on said disk for automatically connecting the inlet circuit to one of the outlet circuits, when the other of the outlet circuits is de-energized, and

terminal contacts carried by said disk disposed for engagement by the contacts of a power consuming device to be connected to said circuit.

FRED A. RENO. 

